Antifriction bearing spacer

ABSTRACT

This bearing spacer is a substantially cylindrical body with rounded corners joining the end and cylindrical side walls. It has a critical diameter and length so that it properly spaces adjacent bearings and is free to slide and turn about its own longitudinal axis in the bearing races without any tendency to tip or cock. The spacer is composed of a relatively incompressible, high temperature resistant material which gradually transfers a film to the bearing for lubricating them at high temperatures.

United States Patent 1191 Smith [5 ANTIFRICTION BEARING SPACER [75] Inventor: Robert L. Smith, Phoenix, Ariz.

[73] Assignee: The Garrett Corporation, Los Angeles, Calif.

[22] Filed: March 8, 1971 [21] Appl.No.: 121,906

[52] US. Cl ..308/l99 [5 1] Int. Cl ..Fl6c 19/20 [58] Field of Search ..308/l99, 200, 2l9, 230

[56] References Cited UNITED STATES PATENTS 2,041,896 5/1936 McGueerQ ..308/DIG. 5 2,325,088 7/1943 Wright et al ..308/2l5 FOREIGN PATENTS OR APPLICATIONS 453,151 1211948 Canada pans/20o 1 51 Jan. 23, 1973 Primary Examiner-Milton Kaufman Assistant Examiner-Frank Susko Attorney-Herschel C. Omohundro, John N. Hazelwood, Albert J. Miller and Jack D. Puffer s7 7 ABSTRACT This bearing spacer is a substantially cylindrical body .with rounded corners joining the end and cylindrical side walls. It has a critical diameter and length so that it properly spaces adjacent bearings and is free to slide and turn about its own longitudinal axis in the bearing races without any tendency to tip or cock. The spacer is composed of a relatively incompressible, high temperature resistant material which gradually transfers a film to the bearing for lubricating them at high temperatures.

9. Claims, 5 Drawing Figures PATENTEDJAH23 1915 I 3.712.694

1 NVEN TOR.

' 1 ANTIFRICTION BEARING srxcaa BACKGROUND OF THE INVENTION bearings in most instances are complicated and expensive to manufacture and maintain.

SUMMARY An object of this invention is to provide a simple bearing spacer which willreduce friction between the antifriction elements, make the bearings self-lubricating, capable of withstanding either high or low temperatures, simple to fabricate and assemble, and characterized by long life and minimum service requirements.

Another object of the invention is to provide a bearing spacer having a configuration andsize which permit the use of the most economical number of antifriction elements in any particular bearing assembly and'the retention of theelernents and spacers in assembled relationship without fasteners or other additional means.

Still another object of the invention-is to provide a bearing spacer having a cylindrical body with rounded corners joining the endand side walls, the spacer being relatively incompressible and composed of ahigh-ternperature-resistant material from which a lubricating film gradually rubs as the spacer moves around between the races and is contacted by the bearingelements; since the spacer turns about its own longitudinal axis as it moves,no area is exposed to excessive wear and the useful life of the spacer is thusextended.

A still further object of 'the invention is to make the spacer, referred to in the previous paragraph, with predetermined critical dimensions which bear particular relation to theantifriction elements and the bearing races. The selected size relations facilitate the movement of the spacer in the races, the retention of thespacer in assembled relation, andthe prevention of certainundesirable movements of the spacer.

Other objects and advantages .will be apparent from the following description ofbearingconstructions embodying the invention and illustrated in detail in the ac companying drawing.

IN THEDRAWINGS FIG. 1 is a side elevational view, partly in section, of a bearing assembly with spacers embodying the invention incorporated therein;

,FIG. 2 is a vertical cross-sectional view taken through the bearing on the plane indicated by the line 11-1! of FIG. 1; 7

FIG. 3 is a perspective view of a spacer formed in accordance with the invention;

FIG. 4=is a detailed sectional view on an enlarged scale through a bearing with a spacer embodying the inventiom'and FIG. 5 is a similar view showing a slightly modified form of spacer.

Referring more particularly to the drawings, the bearing assembly in the first form of the invention illustrated is designated generally by the numeral 10. This bearing assembly has the usual inner and outer races 11 and 12, respectively, the former having a ball groove 13 1 v the grooves 13 and 14 to maintain the races 11 and 12 in concentric spaced relatively rotatable relationship.

in some instances such relation could be maintained by a plurality of ball elements only, but where the bearing is utilized in regions of elevated temperatures, under load, and difficult or impossible lubrication conditions, spacers are provided to prevent the ball elements from rubbing one another and prematurely deteriorating by galling, pitting, sliding, and/or fracturmg.

According to this invention, a spacer 17 is disposed between each adjoining pair of ball elements 16. Spacer 17 in the preferred form of the invention, is a cylindrical body with a cylindrical sidewall 18, a longitudinal axis 20, end wa lls 21, and rounded corners 22 which fair smoothly into the side and end walls. The spacer is composed of a substantially incompressible, high-temperature-resistant material with lubricative characteristics. One such material found to be highly satisfactory in actual use'is carbon-graphite.

The end walls of the spacer may be flat, but in the preferredform they are made slightly concave, as indicated in FIGS. 1, 3 and 4, which assists in retaining the spacers in assembled relationship with the ball elements.

The enlarged sectional view in FIG. 4 shows that the concave end walls of the spacer are engaged by the ball elements at points spaced slightly from the axial center whereby the rolling action of the balls will cause rotation of the spacer about its longitudinal axis 20 as it moves between the races with the balls. Any wear caused by the sliding motion of the spacer will thus be distributed over a greater area of the spacer and its useful life willbe prolonged. it will also be noted that the length of the spacer is such as to prevent any tendency of the spacer to tip or cook and bind between the races; Any tendency to bind is further reduced by the rounded corners 22.

It will be noted from FIG. 4 that the side wall 18 of the spacer will engage the inner race at a point X substantially midway between the ends of the spacer. When so engaged, the rounded corners 22 will be spaced alimited distance Y, i.e., not more than 0.005 inch from the surface of the ball groove in the outer race. it will be recognized that due to such restricted engagement only slight resistance to movement will be exerted by the spacer. As previously suggested, the slidingengagement of the spacer with the races and ball elements will rub a small quantity of the graphite from the spacer in the form of a lubricating powder. This powder serves to maintain the bearing lubricated without further attention even when the bearing is exposed to elevated temperature conditions. In one application of the bearings they operated satisfactorily at a temperature of 900F and a speed of 25,000 rpm. it is readily apparent that no liquid lubricant or organic polymer have such high temperature capabilities.

A slightly modified form of the invention is shown in FIG. 5. In this form the spacer 24 is not truly cylindrical, since the side wall 25 curves outwardly a limited distance and makes the body somewhat barrel shaped. This curvature of the outer wall slightly decreases the area of engagement of the spacer with the surface of the inner race and makes the body conform, or more closely approach the surface of the ball groove in the outer race. The end walls 26 of this form have been shown as flat, however, concave walls could be employed if desired. Rounded corners 27 between the side and end walls are used as in the form of invention first shown and described. I

The modified spacer is also made of of a resistant incompressible lubricative material as in the first form, so that it may be used in areas exposed to high temperatures where conventional lubricants would fail.

I claim:

1. A spacer separating bearing members in -an antifriction bearing comprising:

a. a solid substantially incompressible body of material having lubricative characteristics and a generally cylindrical configuration; and

b. a rounded corner connecting the generally cylindrical side and each of the end walls of said body, said body having a cylindrical diameter approximately 0.010 inch smaller than the diameter of the bearing members spaced thereby.

2. The bearing spacing means of claim 1 in which the body is composed of carbon graphite.

3. The bearing spacing means of claim 1 in which each end wall of the body is provided with a concave depression.

4. The bearing spacing means of claim 2 in which the body is resistant to temperature approximating 900F.

5. The bearing spacing means of claim 2 in which each end wall of the body is provided with a concave depression.

6. An antifriction bearing comprising:

an outer circular bearing race;

an inner circular bearing race concentric with said outer race;

a plurality of bearing members arranged between said bearing races;

a plurality of cylindrical spacers having a cylindrical surface and opposed end walls, said spacers being interposed between said bearing members such that each end wall is adjacent one of said bearing members, said cylindrical spacers being formed of a substantially incompressible material having lubricative qualities and having the corner formed by the intersection of the cylindrical surface and each of the end walls a rounded comer.

' 7. An antifriction bearing according to claim 6 in which the cylindrical diameter of said spacers is approximately 0.0l0 inch less than the diameter of said bearing members.

8. An antlfriction bearing according to claim 7 In 

2. The bearing spacing means of claim 1 in which the body is composed of carbon graphite.
 3. The bearing spacing means of claim 1 in which each end wall of the body is provided with a concave depression.
 4. The bearing spacing means of claim 2 in which the body is resistant to temperature approximating 900*F.
 5. The bearing spacing means of claim 2 in which each end wall of the body is provided with a concave depression.
 6. An antifriction bearing comprising: an outer circular bearing race; an inner circular bearing race concentric with said outer race; a plurality of bearing members arranged between said bearing races; a plurality of cylindrical spacers having a cylindrical surface and opposed end walls, said spacers being interposed between said bearing members such that each end wall is adjacent one of said bearing members, said cylindrical spacers being formed of a substantially incompressible material having lubricative qualities and having the corner formed by the intersection of the cylindrical surface and each of the end walls a rounded corner.
 7. An antifriction bearing according to claim 6 in which the cylindrical diameter of said spacers is approximately 0.010 inch less than the diameter of said bearing members.
 8. An antifriction bearing according to claim 7 in which the end walls of said spacers are concave.
 9. An antifriction bearing according to claim 7 in which the spacers are of carbon graphite. 